Seaming strip



H. J. HILL SEAMING STRIP April 18, 1967 Filed Feb. 15, 1965 2 Sheets-Sheet l INVENTOR H. J. HILL.

SEAMING STRIP April 18, 1967 2 Sheets-Sheet 2 J, j M j vf INVENTOR.

BY #1.: fr-mensys.

United States Patent O 3,314,119 SEAMHNG STRHP Harvey J. Hiii, Monterey Parti, Calif., assigner to Roberts Consolidated industries, line., City oi industry, Calif., a corporation of Caiitornia Filed Feb. l5, 1965, Ser. No. 432,701 7 Claims. (Ci. 24nd?) This invention is concerned with a device for joining together two pieces of material such as the adjoining ends of two pieces of carpeting and the like.

Conventionally, pieces of carpeting are bound together by sewing and/ or gluing the adjoining pieces to a cloth webbing or tape. Sewing of adjoining carpeting pieces together may result in a high ridge at the seam which is subject to excessive wear with passage of time. Additionally, sewing being principally a manual operation involves high labor costs. Bonding of adjacent carpet pieces together with use of a suitable adhesive is not wholly acceptable because of the required drying time, poor strength, and the inability to readily separate the two carpeting pieces should it becomes necessary after the adhesive has set. It will be appreciated that a somewhat high degree of skill is required on the part of the laborer in both sewing and bonding by adhesive. A desirable carpet seam will resist forces tending to pull the two joined pieces apart and yet permit a limited amount of stretch parallel to the seam, this stretching being necessary to the conventional installation procedures for fioor carpeting. v

It is a principal object of the invention to provide a seaming device which permits joined pieces of carpet to be used immediately after installation.

It is a still further object of the invention to provide a seaming device which when installed strongly resists forces tending to pull the two joined pieces apart and yet permits the necessary and normal stretching of the seam and joined material in a direction paralleling the length of the seam.

It is a further object of the invention to provide a seaming device for the installation of carpeting which device may be installed with a minimum of time and by less skilled labor than required for sewing or gluing.

It is another object oi the invention to provide a seaming device which may be readily removed after installaltion to permit the separation of the joined pieces of material.

It is another object of the invention to provide a seeming device which provides a large number of locking prongs which securely join together the abutting pieces ot material.

It is a further object of the invention to provide a device which provides smooth seams devoid of ridges and which are not subject to excessive wear with passage of time.

It is an object to further provide a device that holds material being seamed further back from the edge than is practical with generally used sewing techniques, this being particularly desirable on material which is loosely woven and subject to edge fraying.

It is still an additional object to provide a seaming device which permits the user to readily locate and relocate the mating materials so that matching patterns and colors are at all times visible and under full control.

It is a further object of the invention to provide a seaming device particularly adaptable for use in seaming of adjoining carpeting pieces and a device which when installed locks even more tightly as the carpet is walked upon.

It is a still further object of the invention to provide an improved seaming device which may be substituted for seaming by adhesives and thus reduce the possibility of costly accidents by careless or inexperienced installers.

. spaced apart positions.

it is `another object of the invention to provide a seaming device ywhich may lbe altered by hand stretching prior to installation to reduce the number of locking prongs to a number meeting the needs of a particular job.

It is a still further object of the invention to provide a seaming device having locking prongs tilted from the vertical generally toward the longitudinal axis of the device, thus providing a seeming device which forces the abutting ends of the adjoining pieces of carpet and the like tightly together when hit with `a hammer or equivalent and more strongly opposes perpendicular forces that may `be applied to the seam.

The seaming device of lthe invention in one embodiment comprises a plurality of juxtaposed sections which are joined together by flexible connecting means. The respective sections of the device are provided with a plurality of prongs. The connecting means hold the adjoining sections in a closely spaced, first position and permit movement of the sections into an extended, spaced apart, second position. The connecting means take the form of narrow flexible straps `which in a rst yposition have portions of their lengths at an angle, preferably perpendicular, to the longitudinal axis of the metal strip. A preferred embodiment utilizes flexible, extendable wires for the connecting straps. The ilexible connecting straps may be stretched to assume an extended second position wherein the adjoining sections are spaced somewhat further apart. In a preferred embodiment of the invention the flexible connecting straps take the form of loops which upon opening or partial opening permit movement of adjoining sections a further distance apart. The juxtaposed sections of the seaming device are desirably parallel both in their initial positions and in their The flexible connecting straps are `generally located adjacent 4the oppositte longitudinal margins of the ymetal strip and are preferably located within the confines of the strip.

Other objects and advantages that may be had with the use of the seeming device of the invention will become more apparent in the following speciiication and drawings in which:

FiG. l is a fragmentary, isometric view of the installation of a carpet employing an embodiment of the scaming device of the invention;

FIG. 2 is a sectional view taken along line 2.-2 of FIG. 1 illustrating adjoining pieces of carpet positioned upon the prongs of the seaming device;

FIG. 3 is a sectional view taken from the same site as that of FIG. 2 but illustrating the prongs in their clinched positions;

PEG. 4 is a plan view showing the seeming device of FIGS. 1-3 with four of the sections of the device having been moved into extended, spaced apart positions;

FIGS. 5-11 are -fragmentary plan views of several other embodiments `ol? the seaming device of the invention with in each instance one of the sections having been 4moved into an extended, spaced apart position;

FIG. l2 is a fragmentary plan view of an embodiment wherein the connecting strap between adjoining sections is connected at different heights to the adjoining sections;

FIG. 13 is a Ifragmentary plan view illustrating the seaming device of FIG. 12 in its extended position;

FIG. 14 is a plan view of an embodiment of the seeming device of the invention employing wire as the connecting straps;

FIG. 15 is a plan View of a preferred embodiment of the seaming device of the invention which utilizes wire for the connecting straps between adjoining sections of the device; and

FIG. 16 is a fragmentary sectional View taken along lines le-lt of FIG. l5.

The embodiment of the seaming device of the invention illustrated in FIGS. l-4 comprises a metal strip liti which is formed or cut to have a plurality of juxtaposed, in this instance parallel, elongated sections 12, held together by narrow, flexible connecting means or straps 14 which take the form of loops 16 in the strips initial unstretched form. The metal strip from which the seaming device is formed is very thin, -iiexible material, preferably steel having a thickness in the range of .005 to .030 inch and preferably within the more limited range of .U-.020 inch. The narrow connecting straps ld are formed, in the particular embodiment illustrated, to permit approximately 50% extension of the strip length by hand stretching with very little spring back.

The elongated sections 12 of the seaming device are provided with a plurality of prongs 18 which are formed or stamped out of the metal of the strip iti. The prongs t8 on the opposite sides of the longitudinal axis 2@ of the seaming device (FIGS. 2 and 4) are formed with their axes tilted preferably approximately 10 from the vertical generally toward the longitudinal axis. With this arrangement, upon vertical hammering of the prongs li?) they will bend generally toward the longitudinal axis or seam as illustrated in FIG. 3 and thus force the two carpet pieces 22 and 24 more tightly together and oppose forces that may later be applied in a direction perpendicular to the seam. Each of the sections 12 is provided on opposite sides of the longitudinal axis of the seaming device with multiple prongs 18 (six in the particular embodiment illustrated). The outermost prongs 25 although tilted as the others slightly toward the longitudinal axis, squarely face that axis. The other prongs 18 in the embodiment illustrated are alternately disposed in opposite directions and at an angle up to about 45 to the longitudinal axis 2t) of the seaming device. All of the prongs 18 may squarely face the longitudinal axis 20 as prongs 25. Every second and third ones of the sections IS has a notch 26 located on the longitudinal axis 20 of the seaming device which aids in the location of the device in the laying of a carpet or its use in other applications.

Various techniques may be evolved in the use of the seaming device of the invention in the laying of the carpet or in other applications. A suitable method for carpet laying involves first truing the carpet edges to be joined to make them substantially straight. On carpets which are loosely woven and the exposed tufts on the edges are loose, the respective edges should be sealed with a fastdrying latex-type material to prevent fraying, a technique practiced by skilled installers even when sewing. The seaming strip 10 is then located on top of the iioor or underlying padding and the opposing edges 2l of the two carpet pieces 22 and 24 are abutted above the seaming strip in such a fashion that they force each other slightly upward. This is done to compensate for the slight movement of each carpet edge away from the other due to the slight angle at the edges of the prongs 18 and to insure suitable contact between the carpet backing and prongs before the prong penetration actually occurs. The carpet pieces 22 and 24 are pressed manually down upon the prongs 18 to prevent separation of the carpet edges and then pounded with a hammer or other suitable device. One convenient way of impaling the carpet upon the prongs 18 is to employ a block of solid material which is struck as an anvil with a hammer. It will be recalled that the prongs 18 are formed with their axes tilted approximately 10 from the vertical toward the seam, and hence, when hammered the prongs bend toward the seam and force the two carpet pieces more tightly together as illustrated in FIG. 3. The carpet as first imp-aled on the prongs 18 prior to the bending over of the prongs toward the seam is illustrated in FIG. 2. The hammering of the prongs 18 to assume the clenched position of FIG. 3 secures the seaming device to the carpet pieces 22 and 24 and prevents accidental removal. One of the pieces of carpet 22 or 24 may be fastened first, followed by locating and fastening of the other carpeting piece. A piece of plywood may be used over the padding and immediately beneath the seaming device to facilitate clinching, this being especially useful where the padding is unusually soft.

The seaming device is not limited to use as described in the preceding paragraph but it may be pushed onto a carpet which is inverted on the floor. A rigid block covering several aligned seaming devices would be desirable in this instance with a metal plate or other hard surface located under the carpet to bend the prongs i8.

The strip or individual sections may be used as reinforcement for a sewn seam, this being especially helpful to prevent visible parting on seams where indivi-dual stitches would not withstand tensions created by stretching tools.

Where it is desired, it is possible to nearly double the strength per foot by stacking one seaming device on top of another with segments of one strip being positioned in the spaces between segments of the other strip. The seaming device may be removed from the carpet baci-f.- ing, if desired, by prying it off. This is a feature not feasible with a glued-to-tape seam, or a sewn seam which is also commonly reinforced with latex adhesive. The seaming device of the invention provides a seam which is normally or usually less visible than that obtainable by sewing in the conventional manner. The improvement is particularly noticeable where the carpet concerned is relatively thin, smooth, and of a single color. The seaming device of the invention will stretch longitudinally in two basic stages because of the flexibility of the connecting straps 14. The connecting straps M in the device of FIGS. 1 4 take the form of extendible loops 116. Because of the extendible loops le, the seaming device may be extended to increase the length of the device by approximately 50%. The stretching of the device to this first stage is done by hand and there is little spring back. It will be appreciated that the seam-v ing device may be used without stretching where the maximum number of sections 12 per foot of seam and the maximum strength are desired. Referring to the' right-hand portion of FIG. 4 it will be seen that the loops 16 in the extended first stage of the device of the inven= tion, are substantially or nearly straight, but even here the connecting straps are still slightly curved following the hand stretching. The remaining curvature of the connecting straps 14 provides for additional movement of the carpet as it is stretched parallel to the length of the seam with the powerful stretching tools that are conventionally used in the trade. During and after each stage of extension, the seaming device, including the connecting straps 14, remains substantially fiat.

The extendible feature of the seaming device of the invention provides several distinct advantages. It permits lessening the cost of the seaming device per linear `foot and reduces the hammering required for the installation of the device. The stretching feature permits the reduction of strength in those areas where the requirement is low. By stretching the seaming device to its full first stage extension or portion thereof, it is possible to reduce the amount of metal underlying the carpet seam and thus provide more resilient action between the carpet and underlying padding. The stretchable feature of the seaming device also facilitates quick fitting of the device to a dimension without meticulous measuring, this being a distinct advantage in an area such as across a doorway.

The connecting straps 14 between the adjoining longitudinal sections 12 of the seaming device are rigid enough to support the weight of a sizable length of the device without permitting appreciable extension. The connecting straps 14 are small enough in cross section to permit vertical bending, thus assuring conformation of the seaming device to uneven floors or padding surfaces. This vertical bendability feature permits adjacent longitudinal sections 12 to move substantially independently of each other, with their planes offsetting to conform to irregular foot pressures on the overlying carpet. The connector straps 14 further serve as handy breakoff points which permit the installer to flex the device several times in order to fatigue and break the metal rather than cutting it with shears or tin snips. The connecting straps 14 are prefer ably recessed inwardly as illustrated in the device of FIG. 4, away from the longitudinal margins of the seaming device and Within the contines thereof. The placing of the connecting straps 14 within the contines of the seaming device protects the straps against damage in packaging, shipping, and general handling. The iiexibility of the seaming device provides a seamed carpet which may be rolled perpendicular to the axis of the seam, this being a distinct advantage where the carpet is removed for cleaning or other reasons. The relatively short lengths of the individual sections 12 and the flexibility of the thin metal material permit the carpet to be rolled parallel to the seam as well. The iexibility of the seaming device permits some twisting of the seam without damage, as will often happen when a carpet is moved through a narrow doorway or other confined area in the process of installation.

If in time, due to flexing of the carpet at the seam, the connecting straps 14 fracture, this causes no harm to the seam since it is the sections 12 which are responsible for holding the seam. This feature also permits small left over scraps of the seaming device to be installed.

The connecting straps 14 may take various forms and may be used in different numbers between adjoining sections 12 of the seaming device of the invention. It will be seen that in all of the connecting straps of the various configurations there is a portion of the length of the strap disposed at an angle to the longitudinal axis of the seaming device. Preferably, the connecting straps 14 take the form of a loop as illustrated in most of the configurations with a portion of the loop being substantially perpendicular to the longitudinal axis of the metal strip or seaming device. In all of the embodiments illustrated except that of FIG. 6, the connecting straps 14 are located adjacent the opposite longitudinal margins of the metal strip 10. Preferably, the connecting straps 12 are within the contines of the device proper but, alternatively, they may he placed exteriorly as are the loops 16 of the device of FIG. 5. In the device of FIG. 6, there is provided a single connecting loop 16 between the adjoining sections 12 and this connecting loop is adjacent the longitudinal axis 2t) of the device, this arrangement permitting maximum twisting of material seamed without harm to the seam. The connecting loops 16 may extend outwardly as in the preferred embodiment of FIG. 4 and as illustrated in the devices of FIGS. 8, 9, and 11. Alternatively,

the loops 16 may extend inwardly as shown in the device of FIG. l0. In the seaming device of FIG. 12, the connecting strap 14 is provided with a non-loop configuration but a configuration in which a portion of the length of the strap is substantially perpendicular to the longitudinal axis 20 of the metal strip 10. In this arrangement the opposite ends of the connecting straps 14 are connected at different heights to the adjoining sections 12. Thus, upon extension of the seaming device to its extended form, the alternate sections 12, while remaining parallel with the adjoining sections, are moved perpendicularly to the longitudinal axis 20 of the device as bes-t seen in FIG. 13. It is thus apparent that the connecting straps 14 may take many forms and may be used in various numbers as long as the major axis of the strap deviates from the longitudinal axis of the strip.

The seaming device illustrated in FIG. 14 comprises a plurality of elongated, parallel, juxtaposed steel sections 12 connected by straps 14 taking the form of crimped Wires which `are spot welded at spaced intervals along their lengths tothe respective sections 12. The wire connecting straps 14 provide approximately 50% extension of the seaming devices length by hand stretching. The connecting straps 14 instead of being formed of crimped wires may be stamped members which are susceptible to hand stretching. The wire connecting s-trap version has the advantage of being easily fabricated with no Waste. In some applications untempered thin steel sections 12 Will be bent upon application of localized pressure. This may be remedied by forming the sections 12 from a mild tempered, thin spring steel which is hard enough to provide the desired resiliency but still soft enough to permit punching of the prongs 18 without cracking due to brit tleness of the material. The connecting wire straps 14 of the embodiment of FIG. I4 have no `appreciable resiliency and are soft enough to permit ready bending.

The prongs 1S of FIGS. 2-14 have a. generally triangular shape which imparts rigidity and facilitates penetration into tough carpet backings. The prongs are tilted from the vertical generally toward the longitudinal axis 29 of the device preferably in the range of approximately 5 to 20 degrees from the vertical, in order that they may be bent toward the seam with the application of vertical pressure. For heavy grade carpeting, the length of the prong is desirably about /lp, of an inch. The prongs are constructed so that they extend through the average carpet backing in order that the hammering or rolling subsequently applied will bend over the tips, thus locking the carpet backing between the hooked tips of the prongs and the base surface of the strip. It will be seen that the prongs are not facing in the same directions nor tilted directly toward the axis of the seam except for the outermost prongs 25 of most of the embodiments.

The seaming device of FIGS. l5 and 16 has proven to be a particularly desirable embodiment and is made up of a plurality of elongated, parallel, relatively narrow juxtaposed sections 12 formed of spring steel and connected by crimped wires 14 which are spot welded to the respective sections 12. The wire connecting straps 14 permit approximately a 50% extension of the seaming device when the straps are in their expanded position. The sections 12 of the particular embodiment of FIGS. 15 and 16 are formed of spring steel and are relatively narrow compared to that `of FIG. 14. Prongs 18 are formed at the edge of the material after first punching small round holes 19 in the material to eliminate rnetal tearing .at the base of the later-formed prongs 18. The prongs 18 also have a somewhat different shape and at their outer ends are turned over slightly as best seen in FIG. 16. The prongs 18 being generally made of relatively stifier material than the embodiment illustrated in FIGS. 2 and 3 do not crimp over when hammered to the same degree as the prongs 18 of FIG. 3. The prongs 18 of the embodiment of FIGS. 15 and 16 bend more at the base and less in the middle area.

Since the device of the invention in its various embodi- Inents is stretchable, the carpet can be stretched after the two pieces of carpet are joined together, thus eliminating any possibility of puckering as frequently occurs in hand sewing when the canpet edges are not properly aligned lbefore and during sewing. The device reduces the need of stretching and temporarily fastening the stretched edges before the seam is made. -It is generally advisable when sewing a searn to turn the two pieces of carpet face down in order to facilitate the operation. Due to the fastening method provided by the new device this awlcward time consuming operation is eliminated.

Although exemplary embodiments of the invention have been disclosed herein for purposes of illustration, it will be understood that various changes, modifications, and substitutions may be incorporated in such embodiments without departing from the spirit of the invention as defined by the claims which follow.

I claim: 1. A seaming device comprising: a thin strip of metal formed into a plurality of parallel sections joined together by flexible, connecting gether by Flexible connecting straps, said connecting straps in their rst positions each having a portion of its length substantially perpendicular to the longitudinal axis of the metal strip and holding adjoining straps located adjacent opposite longitudinal margins sections closely spaced, and each of said flexible of said metal strip with the respective sections being connecting straps having an extended substantially provided with a plurality of prongs, said Hexible straight second position wherein the adjoining secconnecting straps having a rst position holding adtions are spaced apart in parallel relationship, at joining sections closely spaced and an extended, least sorne of said flexible connecting straps being second position holding said sections away from each located adjacent the opposite longitudinal margins other and in spaced apart, parallel orientation.

of said strip.

6. A seaming device in accordance with claim 5 wherein at least sorne of the exi'ble connecting straps connecting adjoining sections are located along the longitudinal axis of said metal strip.

7. A seaming device in accordance with claim S wherein the margin-located flexible connecting straps are located outside the connes of said strip.

2. A seaming device in accordance with claim 1 wherein the flexible connecting straps take the form of loops.

3. A seaming device comprising:

a thin strip of metal formed into juxtaposed, elonlgated sections having a plurality of prongs on both sides of the longitudinal axis of said metal strips with said prongs being tilted toward said longitudinal axis and with the juxtaposed sections being joined together by exible connecting straps, said 2() connecting straps in their rst positions each having a portion of its length at an angle to the longitudilleferences Cited by the Examiner UNITED STATES PATENTS na] axis 0f the metal strip and holding adjoining 471,518 3/1892 BJuong 24-"36 sections closely spaced, and each of said flexible con- 1,0891878 3/1914 Stmhwse necting straps having an extended, more nearly 2,552,114 5/1951 Reinhard- Stmiight Second position wherein adjoining sections 217321579 1/1956 Farr 16-16 are spaced further apart, said exible connecting 10981173 11/1961 G03? et al 161`6 Strap being located adjacent opposite longitudinal $399,058 7/1963 Petmeeu 24""152 marsinsof Said st rip- FoRErGN PATENTS 4. A seaming device in accordance with claim 3 where- 30 1 317 824 1/1963 F in the flexible connecting straps comprise loops located 3 2 9i 1g 3 5/1930 Grrelgtain.

Within the confines of said strip.

5. A seaming device comprising: A 1 a thin strip of metal formed into parallel, elongated WILLIAM FELDMAN P'lmmy Exa'mne" sections having a plurality of prongs and joined to- DONALD A. GRIFFIN, Examiner. 

1. A SEAMING DEVICE COMPRISING: A THIN STRIP OF METAL FORMED INTO A PLURALITY OF PARALLEL SECTIONS JOINED TOGETHER BY FLEXIBLE, CONNECTING STAPS LOCATED ADJACENT OPPOSITE LONGITUDINAL MARGINS OF SAID METAL STRIP WITH THE RESPECTIVE SECTIONS BEING PROVIDED WITH A PLURALITY OF PRONGS, SAID FLEXIBLE CONNECTING STRAPS HAVING A FIRST POSITION HOLDING AD- 